The present invention relates to various plasma processing apparatuses such as a plasma etching apparatus, an ashing apparatus, a film formation apparatus, and a sputtering apparatus and, more particularly, to a plasma processing apparatus excellent in terms of an improvement in uniformity of a plasma generated in the plasma processing apparatus, an increase in plasma generation efficiency, an increase in processing precision, a reduction in damage to a substrate, and the like.
Known plasma processing apparatuses are apparatuses for performing various processes such as ashing, etching, CVD processing, and sputtering in an apparatus of manufacturing a semiconductor integrated circuit. In these apparatuses, a high frequency (RF) induction plasma generation apparatus using a coiled antenna is known as an apparatus for generating a plasma. Further, a plasma processing apparatus is also known, which has a plasma generating electrode (e.g. a parallel plate electrode) installed in its plasma processing chamber.
An example of this RF induction plasma generation apparatus is disclosed in European Pat. Appln. KOKAI No. 379828. The RF induction plasma generation apparatus disclosed in European Pat. Appln. KOKAI No. 379828 has a wall opposing a wafer susceptor consisting of an insulator such as silica glass, and a coiled antenna fixed on the outer surface of the insulator wall. A processing gas is ionized by an RF electromagnetic field formed by flowing an RF current through this antenna, thereby generating a plasma.
An antenna division type RF induction plasma generation apparatus is also disclosed in European Pat. Appln. KOKAI No. 379828. In this antenna division type RF induction plasma generation apparatus, the antenna is constituted by two set of coiled antennas in order to precisely control, over a wide range, a generation region where a plasma is generated. An RF power is applied to each antenna.
This RF induction plasma generation apparatus is used as an apparatus for a charge elimination process of eliminating the charge of a jack, a cleaning process of cleaning the wall of a chamber, an etching process, and the like.
In addition, a parallel plate plasma processing system is known as an example of the plasma processing apparatus having a plasma generating electrode installed in the plasma processing chamber. In this parallel plate plasma processing system, two plate electrodes are opposed in the plasma processing or reaction chamber. One of the plate electrodes has a heater or a cooling line contained therein, and is disposed to mount thereon a to-be-processed object. An RF power is applied between the opposed two plate electrodes, thereby generating plasma of a reactive gas therebetween, which is to be used to, for example, etch the to-be-processed object.
The plasma processing apparatus of the antenna division RF induction type has a technical problem that the plasma is difficult to uniformly generate, and another technical problem that hunting occurs between the divided antennas. In addition, the etching selectivity and the etching shape must be controlled.
The plasma processing apparatus of the parallel plate electrode structure also has technical problems such as the difficulty of plasma's uniform generation, the occurrence of hunting between the electrodes, etc. Moreover, also in this case, the etching selectivity and the etching shape must be controlled.